Chlorodifluoropropyl substituted silanes and siloxanes



United States Patent CHLORODIFLUOROPROPYL SUBSTITUTED SILANES ANDSILOXANES Ogden R. Pierce, Midland, Mich., assignor to Dow ComingCorporation, Midland, Mich., a corporation of Michigan No Drawing. FiledJune 26, 1958, Ser. No. 744,654

4 Claims. (Cl. 260-4482) This invention relates to fluorinatedchlorosilanes and their hydrolysis products.

It is the object of this invention to produce novelorganosiliconcompounds containing both fluorine and chlorine in thesubstituent group. Another object is to provide novel organosiliconcompounds which are useful as improved lubricants. Other objects andadvantages wil be apparent from the following description.

This invention relates to silanes'of the formula in which R is amonovalent hydrocarbon radical or a hydrogen atom, X is of the grouphalogen and 'alkoxy radicals and n has a value from 0 to 2 inclusive.

The silanes of this invention where X is halogen are best prepared byone of two methods. In those cases where R is a saturated aliphatichydrocarbon radical or an aromatic hydrocarbon radical, the compoundsare best prepared by reacting 3-chloro-3,3-difiuoropropene-1 with asilane of the formula R SiHX where R and n are as above defined, in thepresence of an addition catalyst such as organic peroxides,chloroplatinic acid or platinum dispersed on charcoal at a temperatureof from 50 to 300 C. at superatmosphen'c pressure.

Those silanes in which some Rs are hydrogen can be prepared by reactingthe difluoropropene with a silane containing more than one hydrogen,i.e. H SiCl or H Si(OEt) Alternatively they can be prepared by reducinga halosilane of the formula with lithium aluminum hydride. The lattermethod is best for producing silanes with more than one hydrogen persilicon.

Those silanes in-which R is an unsaturated aliphatic hydrocarbon radicalare best prepared by reacting halo silanes of the formula CF ClCH CH SiXwith a Grignard reagent of the formula RMgX where R is an unsaturatedaliphatic hydrocarbon radical. These reactions can be carried out in theconventional manner for employing Grignard reagents.

The silanes of this invention in which X is an alkoxy radical are bestprepared by reacting the corresponding halo silanes of the formula Rn OFzCl CHrCHgSiXa-n with a monohydric alcohol. These reactions are carriedout in the conventional manner for reacting alcohols with halo silanes.

When the halo and alkoxy silanes of this invention are hydrolyzed in theconventional manner for hydrolyzing such silanes, one obtains thesiloxanes of this invention.

These siloxanes are of the formula in which R and n are as abovedefined.

ice

For the purpose of this invention, R can be any mono valent hydrocarbonradicals such as any alkyl radical, such as methyl, ethyl, isobutyl,octadecyl and myricyl; any alkenyl radical such as vinyl, allyl,hexenyl, or octadecenyl; any cycloaliphatic hydrocarbon radical such ascyclopentyl, cyclohexyl, or cyclohexenyl; any aromatic hydrocarbonradical such as phenyl, tolyl, xylyl, xenyl', naphthyl and :anthracyl,and any aralkyl hydrocarbon radical such as benzyl and fl-penhylethyl.

The silanes and siloxanes of this invention can contain from 0 to 2 Rgroups per silicon atom. Thus, the silanes can be of the formulaCClFgCHgCHzSlXa R C FzClCHzCHzSiXz and R2 CFQCICHiCHrSiX together withthe corresponding siloxanes of the unit formula /z,

R C FzClCHrCHzSiO and 2 C FzClC HzCHzSlO .5

in which Z is any monovalent hydrocarbon radical (such as those listedfor R) or hydrogen, and m has a value from 0 to 3 inclusive. Thecopolymers of this invention can be prepared by cohydrolyzing thevarious halosilanes or alkoxysilanes in the conventional manner forpreparing siloxane copolymers.

This invention includes within its scope copolymers of the .fiuorinatedsiloxanes of this invention with any proportion of hydrocarbonsubstituted siloxanes. For example, the proportions of the fluorinatedsiloxane can range from .001 to 99.999 mol percent of the total c0-polymer; the remaining units being those of the formula where Z and mare as above defined. I

The silanes employed in this invention are useful as water repellingagents and as intermediates in the preparation of the siloxanes. Thesiloxanes of this invention, both homopolymers and copolymers, areuseful as dielectric fluids and lubricants.

The following examples are illustrative only and should not be construedas limiting the invention which is properly delineated in the appendedclaims. In the specification, the following abbreviations are employed:Me for methyl, Et for ethyl, and Ph for phenyl.

EXAMPLE 1 A mixture of 3,3,3-trifluoropropene-l and 3-chloro-3,3-difluoropropene-1 was reacted with methyldichlorosilane in thepresence of chloroplatinic acid in amount of 3.6 grams per hundredpounds of mixed propenes at a temperature of about 250 C. undersuperatmospheric pressure. The resulting product was fractionated andthere was obtained the compound M (lFzClCfi-zcHrsi h boiling point 152C. at 750 mm. and having a specific gravity of 1.307 at 25 C. and arefractive index at 25 9 C. of 1.4138.

The chlorosilane was dissolved in toluene and hydro- Me C'FiOIOHaCHzSiOThis fluid was found to be an excellent lubricant for steel on steelsurfaces.

EXAMPLE 2 Y When 1 mol of CClF CH=CH is reactedwith 1 mol of thefollowing silanes in the presence of chloroplatinic acid under theconditions of Example 1, the following fluorosilanes are obtained. Whenthese are hydrolyzed in toluene solution in accordance with theprocedure of 4 EXAMPLE 5 When 1 mol of the silane CF ClCH CH SiCl isreacted with 1 mol of vinyl magnesium bromide in tetra- 5 hydrofurane,the silane CH=OH C FzClCHrCHzSiCh is obtained. When this silane ishydrolyzed in toluene solution a fluid siloxane having the unit formulaCH=CH2 C FaClCHaCHniO is obtained. That which is claimed is:

1. A silane of the formula in which R is selected from the groupconsisting of monovalent hydrocarbon radicals and hydrogen atoms, n hasa value from 0 to 2 inclusive and X is selected from the groupconsisting of halogen and alkoxy radicals.

2. A composition in accordance with claim 1 where Example 1, thefollowing siloxanes are obtained. R is methyl and X is chlorine.

Table Silane Fluorosilane Slloxane l H i H HzSiClz CFaClCHrOHzSlChCFzCICHzCHaSlO Hslola CFzClCHzCHzSiCla CFzClCHzCHzSlO Ph Ph PhSlHClz CFCICHnCHgSiCh CFzClCHzCHzSlO M92 7 Me: Me SlHCl CFgClOHzGHzSlClCFlClUHzCHQSlQs V CaHu 0 0511118111011 CFaClCHzCHzSlCln OFICIOHZCHflSlOH l CgH5COH4SlCl: CF2OlCH20Hz(CsH5CaH4) S101: CFaC1CHnCH2(CaH5CuH4) SlOC1sHa1 CraHtv OuHaSiHClr CFzCIOHzCHaSlOh; CFzClCHzCHzSlO HSIF;CFzClCHzCHzSlFL CFiClCHzCHgSlOM" 'No reflux with KOH.

, "Hydrolyzed with sodium bicarbonate solution in amount sulficlent toneutralize the HF produced.

EXAMPLE 3 7 When 1 mol of tribromosilane is reacted with 1 mol of3-chloro-3,3-difluoropropene-1 in the presence of a small amount oftertiary butylperbenzoate at a temperature of 90 .C., the composition CFClCH CH siBr is obtained.

' EXAMPLE 4 When the silane Me 0 FgClCHzCHgSlCh is reacted with thefollowing alcohols at a temperature below C. in the absence of iron, thefollowing alkoxy silanes are obtained.

Alcohol Alkoxy Sllane Me i Methyl CFzClCHzCHzSKOMBh Isopropyl CFzClCHzHz KOCHMBz):

' r Me 7 Octadeey1. OFzClCHzCHzSl (O O 13H)! 3. A siloxane of the unitformula in which R is selected from the group consisting of vmonovalenthydrocarbon radicals and hydrogen atoms, and n has a value of 0 to 2inclusive.

a 4. A composition in accordance with claim 3 in which vR is methyl.

References Cited in the file of this patent v, UNI TED STATES PATENTS2,715,113 Gordon Aug. 9, 1955 OTHER REFERENCES

1. A SILANE OF THE FORMULA
 3. A SILOXANE OF THE UNIT FORMULA